Ginsberg J S, Hirsh J
Department of Medicine, McMaster University, Hamilton, Ontario, Canada.
Drugs. 1988 Oct;36(4):505-12. doi: 10.2165/00003495-198836040-00007.
Pregnant women pose special problems when deciding upon optimal anticoagulant therapy. Heparin does not cross the placenta and is probably safe for the fetus. Long term heparin therapy is occasionally associated with maternal haemorrhage and rarely with symptomatic osteoporosis. Coumarin derivatives, however, cross the placenta and are potentially teratogenic, particularly in the first trimester. Neonatal infant haemorrhage is a possibility if warfarin is administered to the pregnant mother near term. For the prevention and treatment of venous thromboembolism, heparin is the anticoagulant of choice since its safety and efficacy are well established. For the prevention of systemic embolism associated with prosthetic heart valves or valvular heart disease, the efficacy of heparin has not been established. Nevertheless, 12-hourly subcutaneous heparin in doses to prolong a mid-interval activated partial thromboplastin time (aPTT) to 1.5 times control is likely to be effective and safe. An alternative is to use heparin for the first trimester, change to warfarin until the middle of the third trimester, then to restart heparin until term. However, before warfarin is used in pregnant patients, the risks should be carefully explained to the patient to help avoid medicolegal problems. Warfarin can be safely used postpartum by the breast-feeding mother.
在决定最佳抗凝治疗方案时，孕妇存在特殊问题。肝素不会穿过胎盘，对胎儿可能是安全的。长期肝素治疗偶尔会与母体出血相关，很少会与有症状的骨质疏松症相关。然而，香豆素衍生物会穿过胎盘，具有潜在致畸性，尤其是在孕早期。如果在临近足月时给孕妇使用华法林，新生儿有出血的可能性。对于静脉血栓栓塞的预防和治疗，肝素是首选抗凝剂，因为其安全性和有效性已得到充分证实。对于预防与人工心脏瓣膜或瓣膜性心脏病相关的全身栓塞，肝素的疗效尚未确定。尽管如此，每12小时皮下注射肝素，使中间值活化部分凝血活酶时间（aPTT）延长至对照值的1.5倍，可能是有效且安全的。另一种选择是在孕早期使用肝素，在孕晚期中期之前改用华法林，然后在足月前重新使用肝素。然而，在孕妇中使用华法林之前，应向患者仔细解释风险，以避免医疗法律问题。母乳喂养的母亲产后可以安全使用华法林。
